1. A look on a person's face that conveys a thought or feeling: David's mother listened to him with an expression of disbelief as he was trying to explain how he fell into a mud puddle and got so filthy.

Usually when someone grins or smiles, he or she is making an expression of happiness, pleasure, or satisfaction.

2. A presentation of one's feelings or opinions: In a democracy, everyone should have the freedom of expression regarding his or her views about the government.

The convicted criminal showed an expression of disappointment as the judge sentenced him to life in prison.